1. Field of the Invention
The present invention relates to electronically controlled actuators and more specifically to electronically controlled actuators having Hall Effect sensors.
2. Description of the Known Technology
Automobiles are equipped with electronically controlled actuators to open and close the doors of various passageways located throughout the automobile. These passageways may include heating, ventilation, air conditioning passageways, or air passageways to the intake manifolds of internal combustion engines. These actuators will open and close the door of a passageway by rotating an output shaft connected to the door. The actuator determines if the output shaft has rotated the door to a fully opened or to a fully closed position by monitoring the output of a Hall Effect sensor configured to monitor a magnetic field created by a magnet coupled to the output shaft. This magnetic field will vary with the position of the output shaft.
The magnetic field produced by the magnet may vary as the temperature of the magnet changes. To overcome this problem, Hall Effect sensors have been developed that compensate their output based on a change in temperature. Compensated Hall Effect sensors, however, are more costly than uncompensated Hall Effect sensors and are only used with Samarian cobalt (“SmCo”) magnets, which are more costly than other types of common magnets, such as neodymium iron boron (“NeFeB”) magnets.
Thus, there exists a need for a solution that compensates the output of an uncompensated Hall Effect sensor using either a NeFeB magnet or other type of common magnet.